Dexia luzonensis ( Townsend, 1928 )

Zhang, Chun-Tian, Shima, Hiroshi & Chen, Xiao-Lin, 2010, A review of the genus Dexia Meigen in the Palearctic and Oriental Regions (Diptera: Tachinidae) 2705, Zootaxa 2705, pp. 1-81 : 53-54

Dexia luzonensis ( Townsend, 1928)

Asbellopsis luzonensis Townsend, 1928: 379 .

Dexi a luzonensis: Crosskey 1976: 179 . — Crosskey 1977: 603 (catalog).

Diagnosis. Gena more than 1/2 times as wide as eye height; thoracic dorsum with 4 longitudinal vittae; 3 presutural and 3 postsutural dorsocentral setae; 2 katepisternal setae; lower calypter with long fringe; costal spine strong; tibiae reddish yellow; abdominal tergite 3 and 4 without discal setae.

Description. Body length. Female: 8.8 mm.

Female. Head with pale yellowish white pruinosity, upper fronto-orbital plate yellowish; antenna and arista yellow; palpus yellow. Frons about 0.37 times as wide as head width; frontal vitta 0.75 times as wide as fronto-orbital plate at middle; parafacial nearly parallel-sided, about 2.6 times as wide as 1st flagellomere; face well concave, facial carina long and low, sharp on ridge; lower margin of face not produced forward; gena about 0.57 times as wide as eye height; occiput weakly bulged. Inner vertical seta about 2/3 as long as eye height; outer vertical seta fine, about 1/2 as long as inner seta; ocellar seta fine, slightly less than 2/3 length of inner vertical seta; 6−7 frontal setae, lowest seta nearly level with base of antenna; 1 prevertical and 2 proclinate orbital setae, the former slightly shorter than inner vertical seta and anterior seta of the latter very strong; fronto-orbital plate only with a few fine short hairs; gena with a few minute black hairs on lower portion; vibrissa inserted nearly level with lower margin of face. Antenna falling short of lower margin of face by about 1/2 length of pedicel and 1st flagellomere together; 1st flagellomere about 4 times as long as pedicel; total width of arista including plumosity about twice as wide as 1st flagellomere. Palpus slightly shorter than 1st flagellomere.

Thorax black, postpronotal lobe, notopleural area and narrow anterior portion of scutellum reddish; scutum with dense yellowish gray white pruinosity, 2 broad outer and 2 narrow inner longitudinal vittae on presutural area, outer vitta about 4 times as wide as inner one; scutellum with brownish pruinosity on anterior 1/2; pleura with dense pale yellowish white pruinosity. 2 postpronotal setae; 1 presutural and 1 postsutural acrostichal setae; 3 presutural and 3 postsutural dorsocentral setae; 2 postsutural intra-alar setae, anterior one very fine; 2 supra-alar setae, prealar seta absent; 2 katepisternal setae, katepisternum with dense fine short hairs on posterior portion; discal scutellar seta fine. Wing hyaline, evenly pale brownish tinged; tegula reddish brown, pale at base; basicosta brown; lower calypter pale brown, with dense long fringe on outer margin. Costal spine longer than r-m crossvein; vein M from dm-cu crossvein to its bend slightly more than twice distance between the bend and wing margin, appendix 0.5 times as long as r-m crossvein. Legs reddish yellow, tibiae darkened basally and distally; tarsi and claw black. Fore tibia with 2 anterodorsal and 2 posterior setae; hind tibia with 3 anterodorsal, 2 posterodorsal and 2 ventral setae.

Abdomen reddish yellow, dark brown on anterior and posterior margin of syntergite 1+2, mid dorsal triangular portion and posteior 1/3−1/4 of tergite 3, mid dorsal longitudinal area and posterior 2/3 of tergite 4; dense whitish pruinosity on anterior 1/5 of tergite 3, 2/5 of tergite 4 and 1/2 of tergite 5. Hairs fine rather sparse and recumbent, absent on pruinose portion of tergites 3 to 5; syntergite 1+2 with 1 lateral marginal seta, without median marginal setae; tergite 3 with 2 strong median marginal and 2 lateral marginal setae; tergites 4 and 5 each with a row of strong marginal setae; tergites without discal setae.

Male. Unknown.

Type material examined. Holotype female of Asbellopsis luzonensis Townsend , PHILIPPINES, Los Baños , Luzon, Baker ( USNM).

Distribution. Philippines (Luzon).

Remarks. This species is similar to D. flavida , but differs from it in having broad gena which is more than 1/2 eye height, distinct black inner vittae on postsutural scutum, more broad pruinosity on abdominal tergites, and dense yellowish white pruinosity on anterior 1/2 of tergite 5. We have not seen a male of this species.